Storage-battery system



Dec. 11 1923. 1,477,197

R. H. SULLIVAN STORAGE BATTER]! SYSTEM Filed Jul 1922 at each Patented Dec. 11, 1923.

UNITED STATES PATENT OFFICE.

RAYMOND H. SULLIVAN, OF ROCHESTER, NEW YORK, ASSIGNOR TO NORTH EAST ELECTRIC COMPANY, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

STORAGE-BATTERY SYSTEM.

Application filed July 26, 1922. Serial No. 577,592.

To all whom it may concern:

Be it known that I, RAYMOND H. SUL- LIVAN, a citizen of the United States, residing at Rochester, in the county of Monroe and State of New York, have invented certain new and useful Improvements in Storage-Battery Systems; and I do hereby declare the following to bea full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to a system in which a storage-battery is charged by a direct-:cun rent generator, which is driven at variable speed, as in the case of a generator used on a motor-vehicle. In such a system it. is common to interpose an automatic cut-out relay between the generator and the battery, adjusted to open the charging-circuit whenever the E. M. F. of the generator falls below that of the battery, owing to reduction in speed of the generator.

In every direct-current generator, and

particularly in a generator in which a third or auxiliary brush is used for regulation, the

E. M. F. passes through several fluctuations rotation of the armature, these fluctuations being regularly recurrent. Un-

der most conditions of operation these fluctuations are negligible. When the generator is running at a speed, however, which is barely suflicient to hold the cut-out closed, the effect of the fluctuations becomes apparent in the cut-out, causing the latter. at times, to have a vibratory movement and to produce noise and to spark at the contacts.

The object of the present invention is to avoid the vibratory movement. of the cutout, just described; and I have discovered that this may be accomplished by providing a hy-pass around the series winding of the cut-out, of such characteristics that it will by-pass the recurrent fluctuations in current, without seriously reducing the mean current effective in the winding.

' The accompanying drawing is a diagrammatic representation of a storage-battery system embodying the invention.

The invention is illustrated as embodied in a system including a generator I having main brushes or terminals 2 and a third brush 4 through which the winding 5 is fed in the usual manner. terminals are connected with main field- The con

3, and,

.series-winding 10 of the cut-out and hence to the storage-battery 1 1, returning to the generator through the main-conductor 7. The cut-out has also the usual shunt or voltage winding 12, which causes the arma ture to move to circuit-closing position Whenever the E. M. F. of the generator rises to a predetermined point.

The shunt or by-pass of the present invention is a resistance-device 13 connected in parallel with the series-windin 10 of the cut-out. This device may be 0 any convenient form or material except that it must be non-inductive. A short piece of slender resistance-wire is usually sufficient, and its exact resistance is not important, so long only as it is substantially greater than that of the serieswinding 10.

In so far as the steady or mean current through the relay is concerned, the impedanceof the resistance-device 13 is great in comparison with that of the series-wind-- ing, and most of the current therefore passes through the latter. With respect to the rapidly recurrent fluctuations of current, however, the impedance of the series-winding is much the greater, owing to its inductance, and these fluctuations are therefore shunted through the resistance-device In this way the current in the series-winding is heldsteady even when the relay is near its critical point and the fluctuations are large in proportion to the total current passing through the series-winding.

The invention claimed is:

In a storage-battery system comprising a generator, a storage-battery connected in circuit therewith to be charged thereby, and a reverse-current cut-out interposed in the connections between the generator and the battery and provided with a winding-in series with its contacts. the combination, with the cut-out, of a conductor connected in parallel with said winding and having relatively high resistance but low impedance with respect to the recurrent fluctuations in current due to commutation in the generator.

RAYMOND H. SULLIVAN. 

